Fix inference stalling

[gitttt-1234]

This PR resolves an inference stalling issue. Previously, when users interrupted execution with Ctrl+C, the SIGINT signal was caught but the Python process continued hanging. With this fix, the process now exits cleanly when interrupted.

[codecov]

Codecov Report

❌ Patch coverage is 85.50725% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.52%. Comparing base (ff91433) to head (913e862).
⚠️ Report is 37 commits behind head on main.

Files with missing lines	Patch %	Lines
sleap_nn/inference/predictors.py	85.07%	10 Missing ⚠️

❌ Your patch status has failed because the patch coverage (85.50%) is below the target coverage (95.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #331      +/-   ##
==========================================
- Coverage   95.28%   93.52%   -1.77%     
==========================================
  Files          49       49              
  Lines        6765     6931     +166     
==========================================
+ Hits         6446     6482      +36     
- Misses        319      449     +130     

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